Multifaceted impacts of sustainable land management in drylands: A review

Biophysical restoration or rehabilitation measures of land have demonstrated to be effective in many scientific projects and small-scale environmental experiments. However circumstances such as poverty, weak policies, or inefficient scientific knowledge transmission can hinder the effective upscaling of land restoration and the long term maintenance of proven sustainable use of soil and water. This may be especially worrisome in lands with harsh environmental conditions. This review covers recent efforts in landscape restoration and rehabilitation with a functional perspective aiming to simultaneously achieve ecosystem sustainability, economic efficiency, and social wellbeing. Water management and rehabilitation of ecosystem services in croplands, rangelands, forests, and coastlands are reviewed. The joint analysis of such diverse ecosystems provides a wide perspective to determine: (i) multifaceted impacts on biophysical and socio-economic factors; and (ii) elements influencing effective upscaling of sustainable land management practices. One conclusion can be highlighted: voluntary adoption is based on different pillars, i.e. external material and economic support, and spread of success information at the local scale to demonstrate the multidimensional benefits of sustainable land management. For the successful upscaling of land management, more attention must be paid to the social system from the first involvement stage, up to the long term maintenance.

Source apportionment and dynamic changes of carbonaceous aerosols during the haze bloom-decay process in China based on radiocarbon and organic molecular tracers

Fine carbonaceous aerosols (CAs) is the key factor influencing the currently filthy air in megacities in China, yet few studies simultaneously focus on the origins of different CAs species using specific and powerful source tracers. Here, we present a detailed source apportionment for various CAs fractions, including organic carbon (OC), water-soluble OC (WSOC), water-insoluble OC (WIOC), elemental carbon (EC) and secondary OC (SOC) in the largest cities of North (Beijing, BJ) and South China (Guangzhou, GZ), using the measurements of radiocarbon and anhydrosugars. Results show that non-fossil fuel sources such as biomass burning and biogenic emission make a significant contribution to the total CAs in Chinese megacities: 56±4 in BJ and 46±5% in GZ, respectively. The relative contributions of primary fossil carbon from coal and liquid petroleum combustions, primary non-fossil carbon and secondary organic carbon (SOC) to total carbon are 19, 28 and 54% in BJ, and 40, 15 and 46% in GZ, respectively. Non-fossil fuel sources account for 52 in BJ and 71% in GZ of SOC, respectively. These results suggest that biomass burning has a greater influence on regional particulate air pollution in North China than in South China. We observed an unabridged haze bloom-decay process in South China, which illustrates that both primary and secondary matter from fossil sources played a key role in the blooming phase of the pollution episode, while haze phase is predominantly driven by fossil-derived secondary organic matter and nitrate.

Some Law and Economics of Historic Shipwrecks

This paper examines how US and proposed international law relate to the recovery of archaeological data from historic shipwrecks. It argues that US federal admiralty law of salvage gives far less protection to historic submerged sites than do US laws protecting archaeological sites on US federal and Indian lands. The paper offers a simple model in which the net present value of the salvage and archaeological investigation of an historic shipwreck is maximized. It is suggested that salvage law gives insufficient protection to archaeological data, but that UNESCO's Convention on the Protection of the Underwater Cultural Heritage goes too far in the other direction. It is also suggested that a move towards maximizing the net present value of a wreck would be promoted if the US admiralty courts explicitly tied the size of salvage awards to the quality of the archaeology performed.

Mechanism of methylation gene reactivation in human cancer cells

Epigenetic silencing of tumor suppressor genes by DNA hypermethylation at promoter regions is a common event in carcinogenesis and tumor progression. Abrogation of methylation and reversal of epigenetic silencing is a very potent way in cancer treatment. However, the reactivation mechanisms are poorly understood. In this study, we first developed a cell line model system named YB5, derived from SW48 cancer cell line, which bears one copy of stably integrated EGFP gene on Chromosome 1p31.1 region. The GFP gene expression is transcriptionally silenced due to the hypermethylated promoter CMV. However, the GFP expression can be restored using demethylating agent 5-aza-2' deoxycytidine (DAC), and detected by FACS and fluorescent microscopy. Using this system, we observed the heterogeneous reactivation induced by DAC treatment. After flow sorting, GFP negative cells exhibited similar level of incomplete demethylation compared to GFP positive cells on repetitive LINE1 element, tumor suppressor genes such as P16, CDH13, and RASSF1a, and CMV promoter as well. However, the local chromatin of CMV-GFP locus altered to an open structure marked by high H3 lysine 9 acetylation and low H3 lysine 27 tri-methylation in GFP positive cells, while the GFP negative cells retained mostly the original repressive marks. Thus, we concluded that DAC induced DNA hypomethylation alone does not directly determine the level of re-expression, and the resetting of the local chromatin structure under hypomethylation environment is required for gene reactivation. Besides, a lentivirus vector-based shRNA screening was performed using the YB5 system. Although it is the rare chance that vector lands in the neighboring region of GFP, we found that the exogenous vector DNA inserted into the upstream region of GFP gene locus led to the promoter demethylation and reactivated the silenced GFP gene. Thus, epigenetic state can be affected by changing of the adjacent nucleic acid sequences. Further, this hypermethylation silenced system was utilized for epigenetic drug screening. We have found that DAC combined with carboplatin would enhance the GFP% yield and increase expression of other tumor suppressor genes than DAC alone, and this synergistic effect may be related to DNA repair process. In summary, these studies reveal that reversing of methylation silencing requires coordinated alterations of DNA methylation, chromatin structure, and local microenvironment. ^

Behavioral journalism newsletters to increase employee participation in a free worksite wellness center

Background. Providing an worksite fitness center for employees is an effective setting to increase an adult’s levels of physical activity, demonstrably reducing health care costs and elevating employee productivity. Increasing compliance and adherence among employees to consistently utilize an onsite facility remains a challenge.^ Purpose. To illustrate if two electronic behavioral journalism newsletters can increase employee participation in a free worksite wellness center.^ Design. A randomized control trial was implemented. ^ Setting. A large petroleum-producing corporation located in Houston, Texas Subjects.70 full or part time employees that had checked into visited the wellness center during September, October, and November 2009. ^ Intervention. Two behavioral journalism newsletters were created based on authentic community member role model interviews. Newsletters were distributed to intervention group participants via company email. Intervention and control group participant’s visits to the wellness center were monitored via a key card check in system at the facility for two weeks following the newsletter intervention.^ Analysis. Count variable statistics were used to identify rate differences between the intervention and control group wellness center visits. A binomial test for equality of proportions was used to identify differences between participants that had at least one visit to the wellness center compared with those with none.^ Results. Both intervention and control groups had a baseline of zero wellness center visits. The control group had a mean visit rate 0.441 and the intervention group had 0.857. A 0.416, almost one half more visits were found among the intervention group.^ Conclusion. This study indicates that behavioral journalism newsletters featuring a role model from within the worksite population can be a cost effective communication method to improve participation in an onsite wellness center. ^